Heated hair curling brushes are generally used as hair styling devices. They include a gripping handle and a brush section. The handle may have means for transmitting line power to the brush section, or may include internal battery means for generating power and transmitting it to the brush section. A switch is usually provided in the handle to control the application of heat. The brush section generally has a heater core or element, a heated surface which contacts the user's hair, and a complement of brush bristles disposed around the heated surface. Power transmitted through the handle generates heat in the heater core, which indirectly heats the surface element.
In using hair curling brushes, hair is curled around the brush section and is heated by the heating surface. The application of heat causes the hair to retain its curl after it has been removed from the brush. The brush bristles are comprised of a relatively non-heat conductive material, and their tips remain relatively cooler than the heated surface element, and properly control the hair as it is curled.
It is desirable to design a brush which provides maximum heat contact with the hair, and does not snag the hair in the brush during use. Present commercially available heated hair curling brushes come in basically two configurations. In one such configuration, the heating surface comprises a series of heat rings, and the brush bristles are on a series of comb rings. The heat rings and comb rings are placed alternately over the heated surface, and are held in place by the handle on one side and a fastener, typically a screw fastener, on the other side. The fit between these parts must be perfect to eliminate any radial cracks around the circumference of the heated surface. If the screw fastener becomes loose for any reason, the rings may separate, and hair may get caught in the radial cracks between them, causing pulling, snagging, and great discomfort to the user.
in another commercially available configuration, the heating surface comprises a series of strips. The brush bristles are also on strips. The heating surface strips and bristle strips are alternately placed around the circumference of the heated surface in an axial direction. Hair is heated at the points where it contacts the heating surface strips. Because the bristle strips interrupt the heating surface strips, however, the hair will never contact the heating element around the entire circumference of the brush section. Thus, maximum energy usage and heating efficiency is not achieved.